How are meteorite falls tracked by cameras?
Networks of automatic all-sky cameras film the night sky. When two or more catch the same fireball, software triangulates its path, works out its orbit, and predicts where any meteorites fell.
Imagine a set of cameras, each with a fish-eye lens that sees the whole sky, spread across a country tens of kilometres apart and recording every clear night. When a bright meteor flashes overhead, several of them catch it from different angles. That is the basic idea of a fireball network.
From each camera's view, software measures the fireball's position against the background stars at many moments. Combining two or more views, it triangulates the path in three dimensions, giving the height, speed and direction of the object. That yields two great prizes. Tracing the path forwards, plus wind modelling for the final unlit dark flight, gives a search area for meteorites. Tracing it backwards gives the meteoroid's orbit around the Sun, showing which region of the Solar System it came from. A meteorite with a known orbit is scientifically far more valuable.
The first meteorite with a photographically measured orbit was Příbram, which fell in Czechoslovakia in 1959. That success inspired the European Fireball Network, followed by programmes in the United States and Canada; the American network recovered the Lost City meteorite in 1970. Australia's Desert Fireball Network now watches the vast Nullarbor region, where dark stones are easy to spot. In Britain, several amateur and professional camera groups joined forces as the UK Fireball Alliance, and their footage led straight to the Winchcombe meteorite in 2021.
Modern systems use cheap digital cameras and automatic detection, and networks increasingly share data internationally. Ordinary people help too: dashcams, doorbell cameras and phone videos have filled in the picture for falls such as Chelyabinsk. Each recovered meteorite with a known orbit is like a sample-return mission that cost almost nothing.